You can do all that in any of the major music programming languages. Max, Pure Data, Csound, Supercollider, all have tons of facilities for this kind of thing.

You can do all that in any of the major music programming languages. Max, Pure Data, Csound, Supercollider, all have tons of facilities for this kind of thing. The Cipriani & Giri books for Max cover working with samples and loops in great detail and are fantastic books.